Interesting. The most recent images show a first stage motor labeled "C120-018", presumably indicating the 18th Castor 120 motor. Previous images showed a Taurus being moved into the 1555 building this past summer. That Castor 120 looked different, and sported a "BF-009" number. Is it the same motor repainted, or a different motor altogether? Perhaps the mid-summer vehicle was a pathfinder, since it has been more than four years since one of these things flew.

EDIT: Answering my own question, the mid-summer images show the first, second, and third stages of the Taurus XL. The November images show the arrival of the Castor 120 motor, which is "Stage Zero". (It has been four years since *I've* seen one of these things too!)

Once again, an Orbital-designed and -build spacecraft is launched on an Orbital-designed and -built LV. And, remember, Launch Vehicle's aren't much of end product unless there is a spacecraft to be launched by them!

By the way, DWT regards OCO as perhaps "the most important spacecraft Orbital ever built, given its long-term impact on the quality of life here on Earth".

The Orbiting Carbon Observatory arrived at Vandenberg Air Force Baseon Nov. 11. It was shipped from spacecraft facilities in Dulles, Va.,by Orbital Sciences, builder of the spacecraft. The following day itwas removed from its shipping container and placed on a test stand atthe Astrotech payload processing facility located on northVandenberg. On Nov. 13, the protective coverings over the spacecraftwere removed so that processing could begin.

Processing of the Taurus launch vehicle is under way by OrbitalSciences in Hangar 1555 on north Vandenberg. Installation of the UHFcommunications antenna occurred this week. Telemetry testing isscheduled for next week. Thermal protection system insulation andelectrical work is also under way on "Stage 0." Preparations are alsounder way at the launch pad to prepare it to receive Stage 0 nextmonth.

Some additional tests need to be performed on the electronics controlunit (ECU) on the first stage. These additional tests are deemednecessary for the vehicle to be fully flight qualified. It is notclear yet how much time this will take, but it is expected to affectthe planned launch date of mid-January. Coordination with the WesternRange will also be necessary to determine the earliest launch dateavailable.

The Orbiting Carbon Observatory arrived at Vandenberg Air Force Base,Calif., on Nov. 11. It was shipped from spacecraft facilities inDulles, Va., by Orbital Sciences, builder of the spacecraft. Thefollowing day it was removed from its shipping container and placedon a test stand at the Astrotech payload processing facility locatedon north Vandenberg.

On Nov. 13, the protective coverings over the spacecraft were removedso that processing could begin. Blanket preparations and edge tapingon the spacecraft were completed and final closeouts began Nov. 19.Mechanical preparations and work on the electronic ground supportequipment were completed today. A protective covering was placedaround the spacecraft.

Processing of the Taurus launch vehicle is under way by OrbitalSciences in Hangar 1555 on north Vandenberg. Installation of the UHFcommunications antenna occurred this week. Telemetry testing isscheduled for next week. Thermal protection system insulation andelectrical work is also under way on "Stage 0." Preparations are alsounder way at the launch pad to prepare it to receive Stage 0 nextmonth.

Some additional tests need to be performed on the electronics controlunit, or ECU, on the first stage. These additional tests are deemednecessary for the vehicle to be fully flight qualified. It is notclear yet how much time this will take, but it is expected to affectthe planned launch date of mid-January. Coordination with the WesternRange will also be necessary to determine the earliest launch dateavailable.

The work to prepare the OCO spacecraft for launch continues to go well. Testing of the spacecraft systems and science instruments is complete. The next step is to fuel the spacecraft and perform flight battery reconditioning.

Testing and prelaunch preparations continue on the Taurus launch vehicle by Orbital Sciences in Hangar 1555 on north Vandenberg. Launch vehicle flight simulations are scheduled to begin during the third week of December.

Some additional testing is being performed on the electronics control unit (ECU) on the first stage deemed appropriate to assure the vehicle is fully flight qualified. Approximately two weeks of additional time in the schedule is necessary to accommodate the testing. The launch is now targeted for no earlier than Jan. 30 and is subject to the availability of the Western Range.

Due to the availability of the Western Range, the launch of OCO is being rescheduled to Feb. 23. A new schedule of spacecraft and launch vehicle processing is currently being developed to support that date.

The work to prepare the OCO spacecraft for launch has gone well. Fueling the spacecraft is expected to occur during the week of Jan. 12.

Testing and prelaunch preparations continue on the Taurus launch vehicle by Orbital Sciences in Hangar 1555 on north Vandenberg. Loading of software into the Taurus flight computer is under way this week.

The work to prepare the OCO spacecraft for launch will resume with preparations for fueling, currently planned for Saturday. Fueling the spacecraft will then be performed next week. A spacecraft limited performance test will follow. The operation to install the payload fairing around the spacecraft is scheduled to begin Feb. 9.

Testing and prelaunch preparations continue on the Taurus launch vehicle by Orbital Sciences in Hangar 1555 on north Vandenberg. A launch vehicle verification test will be performed on Jan. 12 with a flight simulation planned for Jan. 15.

In the Astrotech payload processing facility, fueling of the OCO spacecraft was completed this week as planned. The spacecraft will be placed into the payload fairing on Feb. 7.

On the Taurus launch vehicle in Building 1555 on north Vandenberg, a flight simulation test is scheduled for Jan. 19. Stage 1 is then planned to be mated to Stage 2 on Jan. 22.

Stage 0, the stage providing the initial liftoff thrust, will be hoisted into position at the launch pad on Jan. 28. The payload/upper launch vehicle integrated stack is planned to be hoisted on top of Stage 0 on Feb. 16.

WASHINGTON -- NASA will hold a media briefing on Thursday, Jan. 29, at11 a.m. EST to discuss the upcoming Orbiting Carbon Observatorymission, the first NASA spacecraft dedicated to studying carbondioxide. The televised briefing will take place in the James E. WebbMemorial Auditorium at NASA Headquarters, 300 E St. S.W., Washington.

Set for launch Feb. 23 from Vandenberg Air Force Base in California,the experimental Orbiting Carbon Observatory will map the globaldistribution of carbon dioxide, the leading human-produced greenhousegas driving changes in Earth's climate.